Interest on undisclosed foreign income under the Black Money Act...

Interest on undisclosed foreign income under the Black Money Act requires non-disclosure of the foreign source in the return; estimation or variation of income from an already disclosed foreign account does not satisfy that condition. Timely filing also prevents interest under the incorporated late-filing computation provisions. Advance-tax interest cannot be imposed without clear statutory language establishing the liability and machinery, and incorporated advance-tax provisions include exemptions for resident senior citizens without business income. Where rectification adds interest linked to the underlying foreign-income addition, the original and rectified orders operate as a composite order, permitting a limited challenge to the connected quantum addition; that issue requires merits consideration.